Order Anura are frogs and toads. Family Bufonidae are "true toads". They are described as having short legs and stout body with rough skin. But usually any Anura that is dryer on land are called toads.
True frogs are in Family Ranidae, they are usually wet and I think this family is described as having dorsolateral ridges all the way to the end of their body. Most Anura that are not considered toads are usually considered frogs.
There are slight differences between Anura families, it is hard to distinguish between frogs and toads unless you are looking at families (there are 21). Bufonidae and Ranidae are true frogs and true toads, then what are the other 19 families? Family Hylidae is tree frogs, but not TRUE frogs. Very confusing and I am not that educated in this, so I can’t give you the specifics within the families. I think you can call all Anura frogs, though.
Also, this is in North America where they call wetter frogs frogs and drier frogs toads. In some countries it is reversed. It’s kind of confusing, but that is the thing with common names vs. scientific names. Hope I helped at least a bit.
(You can look up frog families on wikipedia, I also used my Zoology textbook by Hickman Roberts Larson I'anson 2004)

Man in civilization surveys the creature through the glass of his knowledge and sees thereby a feather magnified and the whole image in distortion. - Henry Benson

Hey Oscar I can also tell you some sorry if I am late.The easiest way to differentiate is by their skin the skin of frogs are smooth and that of toads have lumps on the surface of the skin.These may contain poisonous secretions had hence you better don't touch a toad.Toads can be seen in the summer season in dry land.But frogs always need water.Toads only need water for reproduction.

"Nothing in biology makes sense except in the light of evolution"
-Theodosius Dobzhansky

Tree frogs aren't usually found very close to water, and northern cricket frogs were I live, live in the water but have bumpy skin. It is only easy to distinguish in some cases. Some frogs are even more non-dependent on water then toads, the male carries it's young in it's throat until they develope. Darwin's Frog (Rhinoderma darwinii).

Man in civilization surveys the creature through the glass of his knowledge and sees thereby a feather magnified and the whole image in distortion. - Henry Benson

Since this is a biology forum I am just trying to get the point across that "The use of the common names 'frog' and 'toad' has no real taxonomic justification." http://en.wikipedia.org/wiki/FrogIt's like the word worm, that is used in many different species common names, but only one phyla are true worms.

Man in civilization surveys the creature through the glass of his knowledge and sees thereby a feather magnified and the whole image in distortion. - Henry Benson

Great point, February Beetle! Common names rarely carry much weight in taxonomy; hence the "koala bear," "panda bear," "Tasmanian tiger," and "buffalo wings." Okay, maybe that last one's just a chicken . . .

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